JP2005519105A - Method, reactor and system for producing bisphenol - Google Patents

Abstract

A method for producing bisphenol includes introducing a phenol and a ketone into a fixed, supported catalytic bed reactor system in a downflow mode, reacting the phenol and the ketone to form a reaction mixture, and recovering the bisphenol isomer from the reaction mixture. The preferred bisphenol isomer is bisphenol A, or p,p'-bisphenol A, produced from the reaction of phenol and acetone. The reactor for producing the bisphenol A from the reaction of phenol and acetone includes an ion exchange resin catalyst disposed in a bed and packing randomly distributed throughout the ion exchange resin catalyst to improve heat transfer efficiency and reduce compression of the catalyst bed.

Description

  The present invention generally relates to a chemical reactor system using a rigid packing that provides a predetermined support to the packed catalyst bed. In particular, the present invention relates to the production of bisphenols that are mixed with randomly distributed substantially inert packings that flow down the bed of a cross-linked ion exchange resin catalyst supported by the packings.

  Ensuring optimal physical contact of reactive species is a challenge in chemical reactor design. If improperly designed, a large number of undesired byproducts and large amounts of unreacted reactants can have a significant impact on the economics of the system. In selecting or fabricating the optimum reactor system for a reaction, all types of reactors, reactant and product diffusion, pressure effects, and other factors must be considered.

  Reaction conditions such as reactor residence time and temperature affect the rate of atomic or molecular collisions and affect yield, throughput and selectivity. The pressure is important when the spherical catalyst beads are compressed and deformed by the differential pressure and the liquid throughput is reduced due to the pressure drop limit.

  In reactors with packed beds, fluid flow characteristics are often damaged by flow disruption, or “channeling”. This is particularly noticeable in the upward flow system. Channeling is a condition that can occur due to an inappropriate pressure difference with respect to the height of the bed through which the fluid flows, and that the differential pressure applied to the bed height is too low in addition to the sedimentation of the bed components. Due to multiple. If the bed component contains a catalyst or similar particulate treating agent that allows a random flow of fluid through the bed, the bed portion may short circuit and not be in uniform and reliable contact with the fluid. Such a state can lead to inadequate processing of the charged reactants or insufficient chemical reaction. As a result, early disposal of the catalyst or the treated particles is required, which may impair the value of the catalyst.

  The amount of channeling can be related to the geometry and type of the reactor, the fluid dynamics of the reactants and intermediates and products produced in the reactor, and other factors. In some processes, the optimization of product production by adjusting these parameters is straightforward and straightforward. Elsewhere, these relationships are not so obvious. Using carefully selected catalysts complicates reactor design and reaction control. For example, in US Pat. No. 5,395,857, in the production of bisphenol A (BPA) in a downflow reactor, the degree of cross-linking of the ion exchange resin catalyst directly affects the reactivity and selectivity of the reaction as well as the physical performance of the process. Then it is described. This patent provides the knowledge that by using a two-layer catalyst in which one layer has a degree of crosslinking of 2% or less, the hydraulic effect due to the shape of the catalyst particles and the compression of the catalyst bed due to the pressure can be reduced. It has been. This method aims to increase the volume and time yield of the fixed bed reactor. This design provides improved throughput and yield by improving overall bed stiffness while taking advantage of the low cross-linking catalyst profile of 2% at the top where most of the reactants are converted. The composite catalyst bed described in US Pat. No. 5,395,857 has higher selectivity and activity than others, and a resin-based catalyst having a high degree of crosslinking is desirable because it tends to deactivate and become inactive. For example, in the downflow process, the possibility of the catalyst bed collapsing at a high flow rate due to the low degree of crosslinking and its effect on the physical properties of the catalyst must be taken into account, and strategies to reduce or eliminate this problem. If there is, it is beneficial.

  In addition, channeling and the inefficient contact between the reactants and the catalyst resulting from it often results in significant hindrance to the operation of the packed bed reactor. In particular, operations where significant channeling occurs generally result in lower product yields, requiring early replacement of the catalyst bed, and less efficient utilization of the reactants. As a result, not only the cost of a new catalyst is required, but also a production loss occurs during the suspension of operation, and the distribution cost for replacement, the disposal cost of the used catalyst, and the recovery and recycling of the reactants are required. In addition, significant financial burden can arise as a result of costs associated with efforts to improve catalyst technology. Such costs include the development of alternative reactor geometries, but do not address the problems of existing reactors with inferior geometric features.

  In a configuration in which the reactants flow downward in a reactor having a fixed catalyst bed, the physical performance of the process and the reactivity / selectivity of the reaction may be due to compression due to the pressure in the catalyst bed, depending on the catalyst selected. There is a risk of significant damage. Attempts have been made to utilize structurally rugged catalysts to minimize the compression of the catalyst particles. However, it often leads to a decrease in catalyst activity, a decrease in selectivity, or a shortened life.

Furthermore, there is a direct relationship between the stiffness of the catalyst particles and the predicted active lifetime of those particles. Particles with an open effective pore structure that are characteristic of catalysts with low cross-linking and low-rigidity structures are expected to reduce or eliminate fouling of resin catalysts by tar-like molecules that block access to active acidic sites. it can. On the other hand, particles having a small open effective pore structure and high rigidity are excellent in resistance to compression, but may cause early deactivation of the catalyst due to fouling, resulting in an increase in cost.
US Pat. No. 5,395,857

  While existing reactor geometries and catalysts are suitable for their intended purpose, there remains a need for improvement, particularly with respect to the effectiveness of the reaction in the downflow reactor and the catalyst itself. Thus, for example, there is a need for a reactor system that can fully exploit the potential of a given resin catalyst by reducing the water pressure limit.

  Disclosed herein are methods, reactors, and systems that utilize packed ion exchange resin catalyst beds supported by discrete inert elements.

  Disclosed as the first embodiment is a method for producing bisphenol, which comprises introducing phenol and ketone into the reactor in a downward flow. The reactor includes an ion exchange resin catalyst bed and packing randomly distributed within the ion exchange resin bed. Phenol and ketone are reacted to form a reaction mixture from which bisphenol is recovered.

  Disclosed as a second embodiment is a method of producing bisphenol that includes introducing phenol and ketone into the reactor system in a downflow, the reactor system filling the downflow chemical reactor and the reactor. And a fixed bed ion exchange resin catalyst. The resin catalyst is a sulfonated aromatic resin having a degree of crosslinking of about 2% by weight or less based on the resin catalyst. The ketone and phenol are reacted in a reactor to form a bisphenol-containing reaction mixture, and bisphenol is recovered from the mixture.

  Disclosed as a third embodiment is a reactor for producing bisphenol A by the reaction of phenol and acetone introduced in a downward flow, the reactor comprising a reaction vessel and ions in the reaction vessel. An exchange resin catalyst bed and a packing randomly distributed throughout the ion exchange resin catalyst bed.

  Disclosed as another embodiment is a supported bed reaction comprising a reaction vessel, an ion exchange resin catalyst into which downflow reactants flow in the vessel, and a packing randomly distributed throughout the ion exchange resin catalyst. It is a vessel.

  Disclosed as yet another embodiment is a system for producing bisphenol A from phenol and acetone that is mixed with an acetone feed stream and an acetone feed stream to form a feed stream mixture. A stream (optionally equipped with a jacket), a cooling device into which the feed stream mixture flows, and a reactor connected in fluid communication with the cooling device. The reactor comprises a reaction vessel having an inlet into which the feed mixture flows in at the upper end and an outlet at the lower end, and a supported catalyst resin bed located between the outlet and the inlet. The catalyst resin bed includes an ion exchange catalyst resin and an inert packing randomly distributed throughout the resin. The system further includes a temperature sensing means in communication with the container, a pressure sensing means in communication with the container, a bypass flow between the inlet and the outlet, and a second phenol feed stream acceptable at the outlet. A product take-off line arranged in fluid communication with the lower end of the reactor. The product removal valve is preferably at the same height as the inlet, and a siphon break is located downstream of the product removal valve.

  Hereinafter, with reference to FIG.1 and FIG.2, the manufacturing method and system of bisphenol and the usage method regarding manufacture of bisphenol are disclosed. Reference is now made to the drawings, which are exemplary embodiments, and like elements / parts are indicated by like numerals. FIG. 1 illustrates the reactor type, scheme and configuration, and FIG. 2 illustrates the system used with the reactor to produce bisphenol A or other desired phenol isomers.

  The reactor contains a supported catalyst bed through which the reactants are flowed into contact with the catalyst to produce the final bisphenol. The flow preferably used is a supported downflow, which promotes a chemical reaction in which the reactants co-flow from high to low and flow through the bed to produce a bisphenol product. Although this method can be applied to the production of all bisphenol isomers, the preferred isomer is p, p'-bisphenol A formed by the reaction of phenol and acetone (dimethyl ketone) in the presence of an ion exchange resin catalyst. The exchange catalyst may be modified with a selected promoter, such as a mercaptan compound, as desired. The reactor is shown at 10 in FIG. 1 and has a bed 14 containing an ion exchange resin catalyst and randomly dispersed packing. A co-current downflow of reactants flows into this bed. The ion exchange resin catalyst is distributed around the packing so that the catalyst is supported in the bed to minimize channeling and compressive forces and optimize the hydraulic performance of the reactor. Any type of reaction vessel used to react the reactants in the presence of a fixed catalyst can generally be used in the practice of the present invention. However, a cylindrical reactor is preferred because of its simplicity.

  The inlet 20 is provided with conventional means for introducing the reactants into the reaction zone of the tube, pipe, jet or other reactor. The reactants are typically distributed to the reaction zone by perforated tubes, sparger arms or similar or conventional fluid distribution means. The bottom 42 of the reactor is preferably filled with agglomerates. The amount of such aggregates is not critical to the present invention. However, there should be sufficient agglomerates to support the reactor contents. Agglomerates may consist of any material that is substantially inert to the reactants and products produced in the reactor. Preferably, the agglomerates are composed of silica sand, silica-based gravel, ceramic balls or combinations thereof.

  The reactor shell 16 has an inlet 20 at the upper end and an outlet 24 at the lower end. The inside of the shell may be vented to atmospheric pressure through a vent line (not shown), but normally the operation is performed with the vent line closed. Moreover, the shell 16 may be provided with a jacket for accommodating a cooling flow for removing heat generated by the exothermic reaction of the reactants, as desired. The fluid that can be used as the cooling flow is not particularly limited, and includes water, salt water, and a refrigerant.

  In operation, the reactants are poured from the inlet 20 and distributed to the upper surface of the resin catalyst bed. The reactants react as they travel down through the support bed to form the final product. The outlet 24 is in fluid communication with the bed and product removal line 30 which is substantially flush with the inlet so that the reactor can be operated in an overflow manner while being completely filled with liquid. It is in. Sensor means for measuring pressure 34 and temperature 36 may be placed at the inlet and outlet, and additional conditions may be added to selected locations of shell 16 to detect conditions associated with the reaction and to obtain an appropriate reaction profile. Sensors 35 and 37 may be arranged. Placing the inlet and outlet pressure transmitters at the same height in the development reactor so that the static liquid level is equal before and after the packed support bed for accuracy when collecting engineering and design data, And only ΔP due to the floor support. The relationship between ΔP and flow is exponential for compressible catalysts. Information from such sensor means is sent to a controller (not shown) that adjusts selected parameters such as, for example, feed rate (and flow of cooling flow to the jacket, if used).

  The random placement of the packing in the shell provides a support for the resin catalyst and minimizes compression. “Sedimentation” of the catalyst is essential and is also desirable to completely fill the voids in the catalyst bed. The packing prevents the cumulative compressive force (the sum of the force generated by gravity and the viscous resistance due to the descending flow of the reactants) to such an extent that a high conversion rate, high selectivity and long life by the resin catalyst can be realized. The minimization of the compressive force is sufficient for the “wall effect” of the filling element to spread across the floor on a microscopic scale.

  In general, the spherical catalyst beads are confined within the void “inside” (curved inner curved surface) made of adjacent beads, and generate a certain porosity at which flow can occur. In contrast, when these spherical beads are located adjacent to a surface, i.e. a "wall" or baffle, probe or other plane, the porosity resulting from the relative shape of these two surfaces (plane vs. curved) Resulting in a somewhat disproportionate amount of flow at the “wall” than most of the entire floor.

  The floor 14 includes a plurality of discrete inert elements within the shell, resulting in a random arrangement of surfaces that provide a tortuous path for downward reactant flow. These discretes can be made from any rigid, chemically inert, thermally stable material that supports the resin while allowing the reactants to make optimal contact as they flow through the bed. . Optimal contact is generally achieved with objects with a high porosity (eg, objects with a small volume and a large surface area). The porosity of the random filling element used may be 0.6 or more, for example 0.8. Particularly preferred elements have a maximum porosity of 0.98 or higher. When the porosity is high, the filling amount of the resin catalyst can be increased while sufficiently supporting the floor. Theoretically, there is a relationship between the stiffness of the element, the force to resist deformation under load, and the overall “compressibility” of the ring, and thus the compressibility of the entire floor.

  This type of inert random packing interrupts the packing structure of the spherical resin particles and gives a large effective porosity. The porosity of the resin bed alone is usually about 0.36, and increasing this slightly is expected to reduce the pressure drop dramatically. Increased porosity provides a path for “channeling” or “short-circuiting” that shortens the contact time between the reactants and the catalyst, so the reduction in pressure drop caused by increased porosity is more desirable by preventing compression. I can't say that. Increasing the porosity in the catalyst is not as desirable as simply preventing the decrease in porosity due to bead deformation.

  Preferably, the packing consists of a metal cascade ring such as CASCADE MINI-RINGS® available from Koch-Glitsch (Wichita, Kansas, USA). This cascade ring has a porosity of about 0.97. Other objects that can be used include typical column packing elements such as Pall ring, Tellerette ring, Raschig ring, Bell saddle, Interox saddle and any desired combination thereof. Some examples of these are disclosed in U.S. Pat. Nos. 4,404,113 and 4,086,307. In addition to excellent hydraulic properties, the preferred metal cascade ring packing material improves the temperature differential within the reactor. Accordingly, the outlet temperature can be lowered by operating at the same inlet temperature, or the production amount at the same purity can be increased by operating at a higher inlet temperature. Also, the temperature difference between the inlet and outlet of the reactor filled with these elements is smaller than the temperature difference between the inlet and outlet of the unfilled reactor, but the conversion rate of the reactants in each reactor is substantial. be equivalent to.

  Sufficient reactor charge is randomly distributed throughout the catalyst bed. In a preferred embodiment for producing bisphenol A, at least about 25%, most preferably about 30% or more of the catalyst bed height is random (measured under resin catalyst conditions wetted with phenol prior to introduction of the reactants) randomly. Occupied by packings distributed in Similarly, the height of the packing is preferably sufficient to remain throughout the height of the resin bed when the resin swells over time. This height may be about 110% of the catalyst bed height, most preferably 120%. The packing should be close to the height of the resin and is preferably slightly higher (up to about 20%) so that the resin can swell over time, but the cumulative compressive force is greater at the bottom of the floor than at the top. Therefore, it is considered that the filler may be shorter than the resin.

  Any method can be used to randomly distribute the packing. The easiest and most preferred method is to simply place the charge in the reactor and place the catalyst in the reactor and distribute it within the charge void volume.

  Any known acidic ion exchange resin catalyst can be used as the acidic catalyst, and the catalyst is not particularly limited, but is usually a sulfonic acid type cation exchange resin having a crosslinking degree of about 8% or less, and having a crosslinking degree of about 6% or less. Those having a degree of crosslinking of about 4% or less are most preferred. The degree of crosslinking is preferably about 1% or more, more preferably about 2% or more. The resin catalyst is preferably an ion exchange resin catalyst that is at least partially crosslinked, such as a sulfonated aromatic resin having some divinylbenzene crosslinking and some sulfonic acid functionality, such as those disclosed in US Pat. No. 5,233,096. preferable.

  Acidic ion exchange resins are also used for alkylation of phenols (US Pat. No. 4,470,809). When α-methylstyrene is reacted with phenol in the presence of a cation exchange resin catalyst, p-cumylphenol is produced (US Pat. No. 5,185,475), and when mesityl oxide is reacted with phenol, chroman is produced. In use, the individual particles of the resin catalyst are subjected to compressive force due to hydraulic filling, and if the degree of crosslinking is low, the particles have low rigidity and are susceptible to hydraulic deformation. The degree of crosslinking of the ion exchange resin catalyst can be up to about 4%, but is preferably about 2% or less to improve catalyst life.

In the reactor system of the present invention, the catalyst agent is most preferably a sulfonated aromatic resin comprising a hydrocarbon polymer having a plurality of side chain sulfonic acid groups. These are typically crosslinked with 2% or 4% divinylbenzene. Most preferred is a catalyst having a crosslinking degree of 2% or less. In this regard, poly (styrenedivinylbenzene) copolymers and sulfonated phenol formaldehyde resins are useful. Examples of such suitable catalysts are commercially available from Rohm and Haas Chemical as “AMBERLITE A-32” and “AMBERLYST A-121” brand catalysts and from Bayer Chemical as “K1131” brand catalysts. There are sulfonated resin catalysts. The exchange capacity of the acidic resin is preferably about 2.0 meq H ⁺ or more per gram of dry resin. Most preferred is a range of 3.0 to about 5.5 milliequivalent H ⁺ per gram of dry resin. A cocatalyst or catalyst promoter may be used as appropriate. Either bulk or combined catalyst promoters can be used. Many of these are well known in the art.

  The process and reactor of the present invention are particularly suitable for the production of bisphenol A (hereinafter abbreviated as BPA). When the reactor is used for the production of bisphenol A, phenol is usually used in excess with respect to acetone, and the molar ratio of phenol to acetone (phenol / acetone) is usually about 6 mol or more of phenol per mol of acetone, preferably 1 mol of acetone. More than about 12 mol of phenol per mol, about 20 mol or less of phenol per mol of acetone is preferable, and about 16 mol or less of phenol is more preferable per mol of acetone.

  The reaction of phenol and acetone is usually carried out at a temperature sufficient to keep the feed to the reactor in a liquid, preferably above about 55 ° C. Moreover, the temperature of 110 degrees C or less is preferable, 90 degrees C or less is more preferable, and about 85 degreeC is the most preferable. The bed pressure difference when the inlet and outlet pressures are measured at the same height is preferably about 0.1 psig or more, more preferably about 3 psig. Further, the pressure difference is preferably about 35 psig or less, more preferably about 26 psig or less.

  In the above reaction of phenol and acetone, in addition to the liquid reaction mixture containing bisphenol A, reaction by-products such as unreacted phenol, unreacted acetone and water are also part of the reaction mixture.

  Throughout this specification, the term phenol refers to phenols of the formula and selected substituted phenols described in more detail below.

  Similar to bisphenol A, bisphenol obtained by reacting phenol and ketone is represented by the following formula.

In the formula, R ^a and R ^b are halogen or a monovalent hydrocarbon group which may be the same or different, p and q are integers of 0 to 4, and X is of the following formula.

R ^c and R ^d are a hydrogen atom or a monovalent hydrocarbon group, or R ^c and R ^d may form a ring structure, and R ^e is a divalent hydrocarbon group. Specific examples of the bisphenol of the above formula include 1,1-bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane (hereinafter referred to as “1-phenol”). , Bisphenol A), 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, 1,1-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) butane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxy-1-methylphenyl) propane, 1,1-bis (4-hydroxy-t-butylphenyl) Propane, and bis (hydroxyaryl) al, such as 2,2-bis (4-hydroxy-3-bromophenyl) propane And bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclopentane and 1,1-bis (4-hydroxyphenyl) cyclohexane, 6,6′-dihydroxy-3,3 , 3 ', 3'-tetramethyl-1,1'-spiro (bis) indane, 1,3-bishydroxyphenylmethane, 4,4'-dihydroxy-2,2,2-triphenylethane, 1,1 There are '-bis (4-hydroxyphenyl) -meta-diisopropylbenzene and 1,1'-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane.

In addition, bisphenols in which in the above formula is —O—, —S—, —SO—, or —SO ₂ — can also be produced. Examples of compounds that can be prepared include bis (hydroxyaryl) ethers such as 4,4'-dihydroxydiphenyl ether and 4,4'-dihydroxy-3,3'-dimethylphenyl ether, 4,4'-dihydroxydiphenyl sulfide and Of bis (hydroxydiaryl) sulfides such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide And bis (hydroxydiaryl) sulfones such as 4,4'-dihydroxydiphenylsulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone. Of these substances, the production of bisphenol A is particularly preferred.

  The bisphenol as described above can be obtained by a known bisphenol synthesis method by condensation of an appropriate substituted phenol and a ketone in the presence of an acidic catalyst. You may use the phenol which has a structure without the coupling | bonding by X in said formula. Moreover, if the said bisphenol can be obtained, condensation with phenol, formaldehyde, a sulfonic acid, etc. can also be performed.

  The reactants in reactor 10 react to form bisphenol (or BPA when the reactants are acetone and phenol), and a product stream containing bisphenol, unreacted reactants, optionally a cocatalyst, and a small amount of other materials. Exit the reactor as

  The product stream may be sent to a separator, which can be any conventional method for separating such materials. In general, distillation is the simplest and most preferred method. However, other well-known methods can be used separately or in combination with distillation for the separation process.

  The bisphenol product, bisphenol isomer, phenol and a small amount of various impurities are removed from the separator as the bottom product. This bottom product is fed to a further separator.

  Crystallization is the preferred bisphenol separation method, but any method that can be used to separate bisphenol from the mother liquor can be used, depending on the desired purity of the bisphenol product. Once separated, the dehydrated mother liquor containing phenol and bisphenol isomers is returned to the reactor 10 as reactants.

  The bisphenol separated from the mother liquor in the separator can then be sent to yet another separation and purification machine of the bisphenol recovery process. This is especially important when a very pure product is required, such as when producing BPA which is then used to produce polycarbonate. In general, such additional separation can be advantageously performed using techniques such as recrystallization.

  In order to alleviate the problems associated with compression of ion exchange resin catalysts, the resin catalyst bed may further comprise layers of catalysts having different degrees of crosslinking and modification methods or combinations thereof. In particular, the catalyst bed may be prepared from a combination comprising an ion exchange resin catalyst with a high degree of crosslinking at the bottom of the bed and an ion exchange resin catalyst with a low degree of crosslinking at the top of the bed. The degree of crosslinking of the ion exchange resin catalyst near the top of the bed is preferably about 2% or less, and the degree of crosslinking of the ion exchange catalyst resin at the bottom of the bed is preferably more than about 2%.

  In use, the shell or cylinder 16 is filled with a filler and a resin catalyst by alternately charging a predetermined amount of the filler and the catalyst. The catalyst can be wetted with water and “pre” or partially dried beads. Preferably, sand is initially charged at the bottom of the shell as a support and / or filter. In a preferred embodiment, the reactor is filled up to about 1/4 of its height with water and 1/4 of its height with packing elements. The column is then filled with a resin wetted with water, closed, and phenol flowed to dehydrate the resin and shrink into the area occupied by the element. Repeat this procedure for the remaining column height. Additional elements that swell during the reaction are added to the top of the bed. This procedure is performed with phenol if the catalyst has been previously dried.

In this method of producing bisphenol A from phenol and acetone, phenol and acetone are introduced into an ion exchange resin catalyst bed, the phenol and acetone are reacted in the presence of the resin catalyst, and then bisphenol A is recovered from the reaction mixture. Including that. The phenol and acetone are introduced at the top of the bed at a rate sufficient to allow the reaction to proceed with a given yield and selectivity (to facilitate co-current downflow of reactants). The reaction between phenol and acetone is usually carried out at a temperature sufficient to keep the feedstock to the reactor liquid, preferably at a temperature of about 55 ° C or higher. Also preferably, the temperature is about 110 ° C. or less, preferably about 90 ° C. or less. Reactant introduction is generally about 0.1 pounds per hour or more of feedstock per pound of dry catalyst (lb feedstock / hr / lb catalyst), preferably about 1.0 lb feedstock / hr / lb catalyst or more weight time Space velocity (WHSV). Also, about 20 lb feed / hr / lb catalyst or less, preferably about 2.0 lb feed / hr / lb catalyst or less is preferred. The introduction of the reactants typically the floor cross-section per square foot per minute to about 0.1 gallons (gpm / ft ²⁾ or more, preferably about 0.5 gpm / ft ² or more flux rate. A preferred amount is about 2.0 gpm / ft ² or less, most preferably about 0.5 gpm / ft ² or less. The temperature of the reaction can be controlled in part by removing the heat of reaction with a cooling stream flowing through the jacket. However, in the case of plug flow packed beds, the reactor functions almost adiabatically because of the low radial heat transfer. The filling serves to improve heat transfer, thus reducing thermal insulation and improving temperature control. The temperature of the reaction can be up to about 110 ° C, but is preferably limited to about 85 ° C. During steady state operation of the reactor, the differential pressure between the inlet and outlet 24 is about 0.1 pounds per square inch (psig) or more, preferably about 3 psig or more. Moreover, about 30 psig or less is preferable and about 24 psig or less is further more preferable.

  Referring now to FIG. 2, the entire system for producing bisphenol A from phenol and acetone is shown at 50. System 50 includes a premixed feed stream 54 containing phenol, acetone and dehydrated recycle mother liquor, which is initially fed to cooling device 58. This cooled feed mixture is then introduced into the reactor 10 via the inlet line 59. This mixture is then flowed down into the packed catalyst bed 14 of the reactor to form the bisphenol A product. A product stream containing unreacted material and some by-products in addition to the desired bisphenol A flows through the reactor outlet line 63. A second phenol feed stream 62 is connected to the outlet line 63 and can be used to charge the reactor. This outlet line 63 is connected to the product extraction line 30. As already described with respect to FIG. 1, the reactor 10 includes pressure sensing means 35 and temperature sensing means 37 at various locations along the reactor shell. The return line 64 from the cooling device 58 preferably comprises a flow tracking line 72. (Because the material being processed is a solid at ambient temperature, controlled heat is applied to the piping, the reactor and, if necessary, the device to maintain the desired fluid temperature. Known as “tracking” or “jacketed”). The system 50 may further include a siphon break 70 disposed downstream of the product removal line 30. The reactor is vented via line 65. Either or both of the phenol and acetone feed streams may contain impurities recycled from the initial reaction. Impurities originating from the reaction of phenol and acetone can be isomerized in the recycle stream.

Example 1
A reactor shell having an inner diameter of about 21 inches, a cross-sectional area of 2.377 square feet, and a height of 15 feet is packed with a bulk density of 15.3 lb / ft ³ (lbs / ft ³ ) (CASCADE MINI-RINGS®). )) And 2% cross-linked wet ion exchange resin catalyst A-121 from Rohm and Haas, were charged step by step. Between the charges, the reactor was closed and the resin catalyst was dehydrated by flowing a phenol flow with a water content of less than 0.5% through the resin catalyst bed. This stepwise charging and dehydration operation was repeated until the catalyst bed was 10.5 feet high. A total of 329.6 lbs of charge and 3166 lbs of wet resin catalyst were charged. The density of the resin catalyst wet with water is 45.8 wet lbs / ft ³ (about 8.5 “dry” lbs / ft ³ ), and the density of the same resin catalyst dehydrated with phenol is 24.9 “dry” lbs. / Ft ³ . Upon dehydration of the resin catalyst, 592 lbs of “dry” catalyst remained.

  The differential pressure in the vertical height direction (both ends) of the resin catalyst bed was measured at various reactor feed rates. The feed composition was similar to that in Table A, column A. The accelerator used is 3-mercaptopropionic acid at a level of about 800 ppm. Table I shows the measured flow rate versus differential pressure observed in the vertical dimension of the resin catalyst bed.

The table shows the average value, obviously the pressure increases with increasing flow rate, but this increase is mitigated by the support.

Example 2
In a control experiment using the same type of resin without filling, the experimental conditions and feed composition of Example 1 were used. Table II shows the flow rate measured against the differential pressure observed in the vertical dimension of the resin catalyst bed.

Without the support provided by random packing, the compression of the unsupported catalyst bed under increased flow is large, resulting in severe limitations on throughput and hence productivity. Listed are average values.

  FIG. 3 is a comparison between the resin with the filling of Example 1 and no filling of Example 2 under the same conditions. This figure shows that the increase in differential pressure through the bed of compressible resin is mitigated by the packing for the same resin system and experimental conditions.

Example 3
Several experiments were performed at different typical process conditions to measure the temperature difference between the reactor inlet and outlet and the conversion of the reactants. These conditions and the average of several measurements are shown in Table III.

  As can be seen from the above data, the conversion is almost the same for widely varying conditions, but the temperature difference between the inlet and outlet of the reactor filled with the ring is the temperature difference between the inlet and outlet of the reactor without packing. Smaller than. This is not unusual because smaller temperature differences do not favor equal conversions.

  Although described in connection with the preferred embodiment, it will be apparent to those skilled in the art that various modifications can be made without departing from the scope of the invention, and that the elements may be replaced with equivalents. it can. In addition, many modifications may be made to adapt a particular situation or material to the teachings herein without departing from the scope of the invention. Accordingly, the present invention is not limited to the particular embodiment considered best for practicing the invention, but encompasses any embodiment that falls within the scope of the claims.

FIG. 1 is a schematic view of a downflow chemical reactor having a supported ion exchange resin catalyst disposed therein. FIG. 2 is a schematic view of a system for producing bisphenol A by reaction of phenol and acetone with an ion exchange resin catalyst in a supported downflow catalyst bed. FIG. 3 is a graph showing an increase in the differential pressure of the compressible resin bed in comparison with the case where there is a filler.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Reactor 14 Fixed support catalyst bed 30 Product extraction line 34 Pressure detection means 36 Temperature detection means 50 Reactor system 54 Feed stream mixture 58 Cooling device 62 Second phenol feed stream 70 Siphon break

Claims (21)

A method for producing bisphenol, comprising:
Phenol and ketone are introduced into the reactor (10) in a downward flow,
Reacting phenol and ketone to form a reaction mixture;
Recovering bisphenol from the reaction mixture, wherein the reactor comprises packing randomly distributed in the ion exchange resin catalyst bed (14), and optionally comprises a catalyst promoter for sulfur compounds. A method comprising a catalyst bed (14). The process of claim 1, wherein the ion exchange resin catalyst in the bed (14) is crosslinked. The method of claim 2, wherein the degree of crosslinking of the ion exchange resin catalyst is about 4% by weight or less of the resin. The method of claim 3, wherein the degree of crosslinking of the resin is greater than 2% by weight. The method according to claim 2, wherein the degree of crosslinking of the resin is 2% or less. The method of claim 5, wherein the degree of crosslinking of the ion exchange resin catalyst is about 2%. The method of claim 1, wherein the ion exchange resin catalyst is a sulfonated aromatic resin. 8. The method of claim 7, wherein the bound accelerator consists of a portion of the sulfonate group of the sulfonated aromatic resin modified by neutralization with a sulfur-containing compound. 8. The method of claim 7, wherein the bulk accelerator comprises a sulfur-containing compound that is freely dispersed in the reaction mixture. The method of claim 1, wherein the filler comprises an inert material having a void volume of about 0.6 to about 0.98. The filling is selected from the group consisting of a Pall ring, a Berl saddle, an Intalox packing, a Tellerette packing, a Hyperfill packing, a Stetman packing, a Sulzer packing, a Raschig ring, a Koch-Glitsch cascade miniring (registered trademark) and a mixture thereof. The method according to claim 10. The method of claim 10, wherein a majority of the packing consists of a Koch-Glitsch cascade miniring®. The method of claim 1, wherein the accelerator is present as 3-mercaptopropionic acid. A method for producing bisphenol, comprising:
Phenol and ketone are introduced into the reactor system (50) in a downward flow,
Reacting ketone and phenol in reactor (10) to form a bisphenol-containing reaction mixture;
Recovering bisphenol from the mixture, wherein the reactor system (50) comprises a downflow chemical reactor (10) and a fixed bed (14) ion exchange resin catalyst packed in the reactor (10). A fixed bed (14) having a randomly distributed packing, wherein the resin catalyst is a sulfonated aromatic resin having a degree of cross-linking of about 2% by weight or less based on the resin catalyst. ,Method. A reactor (10) for producing bisphenol A by reaction of phenol and acetone introduced in a downward flow manner,
Reaction vessel (10),
A reactor comprising an ion exchange resin bed in a reaction vessel (10), the ion exchange resin catalyst bed (14) including an appropriate promoter, and a packing randomly distributed throughout the ion exchange resin catalyst bed (14). (10). The reactor (10) of claim 15, wherein at least a portion of the ion exchange resin catalyst in the bed (14) is crosslinked. A system (50) for producing bisphenol A from phenol and acetone,
Acetone feed stream,
A phenol feed stream that is mixed with an acetone feed stream to form a feed stream mixture (54);
A cooling device (58) for receiving a feed stream mixture (54),
A reactor (10) connected in fluid communication with a cooling device (58), comprising a reaction vessel (10) having an inlet into which a feed stream mixture (54) flows in at an upper end and an outlet at a lower end. A reactor in which a supported catalyst resin bed (14) is disposed between the outlet and the inlet, the catalyst resin bed (14) comprising an ion exchange catalyst resin and an inert packing randomly distributed throughout the resin. (10),
Temperature sensing means (36) in communication with the container (10);
Pressure sensing means (34) in communication with the container (10);
A bypass flow between the inlet and outlet,
A second phenol feed stream (62) acceptable at the outlet;
A product removal line (30) located in fluid communication with the lower end of the reactor and at the same level as the inlet so that the reactor (10) can be operated in an overflow manner while being completely filled with liquid;
Siphon break (70) located downstream of the product removal valve
A system with The system (50) of claim 17, wherein the catalyst resin defines a substantially uniform porosity across the vertical dimension of the bed between the inlet and outlet. The system (50) of claim 18, wherein the reactor is maintained at a temperature of about 65 to about 85 ° C during the production of bisphenol A. Bisphenol A produced by the method according to claim 1. Phenol and acetone are introduced in a downward flow into a reactor comprising an ion exchange resin catalyst bed (14) comprising a promoter and packing randomly distributed in the ion exchange resin catalyst bed (14);
Reacting phenol and acetone to form a reaction mixture;
Bisphenol A produced by a process comprising recovering bisphenol from the reaction mixture.

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